<!DOCTYPE html>
<html>
  <!-- Test: if input is invalid but it's value hasn't changed, it's not
             affected by :-moz-ui-invalid pseudo-class. -->
  <link rel='stylesheet' type='text/css' href='style.css'>
  <body>
    <fieldset disabled>
      <legend>
        <input class='notinvalid' required>
      </legend>
    </fieldset>
  </body>
</html>
